Combined safety-valve and pressure-gage.



B. B. KEITH.

COMBINED SAFETY VALVE AND PRESSURE GAGE.

APPLICATION FILED MAR. 31, 1913.

1,128,327. Patented Feb.16,1915.

INVENTOR UNITE shares 1 PATEntr OFFICE. I

EDWARD B. KEITH, or wns'r Bnoor/rrIELn, MICHIGAN, ASSIGNOB-OF ONE-HALF 'ro JOHN WATCHPOCKET, F PONTIAC MICHIGAN.

I COMBINED SAFETY-VALVE an]: rnn'ssunn-eacn.

Specification of Letters Patent.

Application filed March 81,1913. Serial No. 757,901.

To all whom it may concern:

a new and Improved Combined Safety- Valve and Pressure-Gage, of which the following is a specification.

' a revoluble stem extending upwardly from.

,an auxiliary valve This invention relates to means for indicating the pressure'in automobile tires and other containers and for limiting the maximum of'such pressure, and its object is to provide asimple and eflicient pressure inwhich may be dicating and limiting device and easily connected to any pneumatic tire, which can be constructed at low cost.

This invention consists in combination with a tire valve, of a fitting on which it is mounted, of an adjustable pressure valve mounted on the fitting and provided with to permit the escape of the air or other fluidwithin the valve; 1

It furtherconsistsfln connection of a fitting connected to thetire or other container,

of a cylindrical indicator casing having a.

flexible diaphragm and an engaging member mounted in the lower-end of the casing,

a spring to resist the presmeans to cause the longitudinally, and

the diaphragm, sure on the diaphragm, stem to turn as it moves .an indicator connected to said stein.

In the'accompanying drawing, Figure 1 is an elevation of this improved device'-' mounted on a wheel. 'Fig. 2 is a central section of the sameparallel to the plane of Fig. 1. Fig. 3 is an elevation of a novel tire tube. Fig. 4 is a plan of the same. Figs. 5 to 7 are details of construction. Fig. 8 is a vertical central section of the diaphragm.

Similar reference characters refer to like parts throughout the several views.

The tire 1, rim 2 and spoke 3 of Fig. 1 are old and well known, as are also the tire tube 4, its head 5 and washer 6 which grip the inner tube 7, the nut 8 to hold down the washer, and the nut 9 to grip the .rim. The tire tube may be shortened ifdesired in order' to bring the combined safety valve and pressure indicator near, the rim;

is a tire valve 14 of any desired construcent .disk 28 of glass held in position by the ring tion roller 38 ;of the indicator 39 andthefigures on bottom of the chamber; movement can be determined. {The cham- V .ber 26 may have a flange 4O toscrew onto the upper end tion which needs no further explanation.

On the arm 12 is screwed a cylindrical body 15 having a tapering seat 16 for the valve- 17, held to its seatby the spring 18; The

valve 17 is preferably provided with a thin rubber face 19 to absolutely prevent leakage.

the central portion of the cross 10. It consists of a diaphragm supporting sleeve25,

an upper indicator chamber26 and a con-' necting sleeve 27, together with the differpartstherein. The chamber 26 has a 29', and its bottom 30 may be vgraduated asindicated "n Fig. 5. Revolubleand slidable in the bottom 30 is a stem 32ihaving an indicator hand-39 at its upper end A tubudPatentedFeb. 1 1915.

"so Thetension of the spring is regulated by V the plug 20, which screws into the upper larextensiong33 on this bottom is'threaded V at its upperflend to receive the nut 34 by means of which the tension on the spring 35 is regulated. Thistubular member 33 is also provided with aspiralslot 36 (Fig. 7)

' in which a pinB? on the stem 32 is movable,

which pin preferably carries an" antifric- It will therefore'be seen that when this, stem 32 is moved'up and down, it willturn by reason of thespiral slot 36 in which the pin 37 moves,- and by means the 26,'th-e amount of p of the connecting sleeve'27. The sleeve 25 which forms the chamber. for the diaphragms has a shoulder 42, as

shown in Fig. 8, on which rest the layers 43, 44 and 45 of flexible. material, preferably sheet rubber, properly 7 desired, separated by the rings 46 and 47, and held in position by the which is pushed down by the sleeve 2 shown in Fig. 2. .A button 49 at the lower reinforced. if

wide ring 48 end of, the stem 32 has a screw threaded end 50 which passes through a hole in the upper layer 43, and carries a nut 52 and washer 5 to unite it to this layer. transverse hold to receive-the pins 54 which The button has a a i I ring 56.

'As the pressure in the bore of the tire engage in a slot 55 in thestem 32, which pins are held in position by the bearing tube 4 increases, and therefore increases in the chamber 57 below the diaphragm formed by the layers 43 44;45, the diaphragm and the button 49, together with the stem 32, will be pushed upward against the Y rectly indicate the pressure under the diaphragm. When the pressure falls, the spring 35 will force down the button 49 and the stem 32, and turn back the hand.

Many of the details of construction may be changed by .those skilled in the art with out departing from the spirit of my invention as set forth in the claims and many of the refinements shown may be omitted.

- When the tire has been removed and it is desired to replace it, a long tire tube is de-' sirable. I therefore prefer to counterbore the tube 4 and thread the outer end to receive the threaded end 60 of an extension 61 shown in Fig. 3, until the part 4: is properly secured in position by means of a nut 9, whereupon the part 61 can be removed and the combined valve and indicator put in position. a

' As the tube 4 is made fiat, as a rule, in order that it can be held while the nut 8 is being screwed down, a resilient washer .63, preferably of rubber, is placed on the tube so that, when it is forced against the tube by the lower cup-shaped end of the fitting 10, a tight joint between fitting and tube will be insured. This device will be exposed to water and mud, and the discharge opening (it in the body 15 of the valve is therefore liable to become plugged. To prevent this,

a small leaf-spring 65 (Fig. 6) ma be secured to the valve-body by means 0 a rivet 66, and carry a small bit of rubber 67 to cover the hole. The construction shown in Fig. 6 is greatly exaggerated in size.

The advantage of this safety valve lies in the fact that the dangerous increase in pressure in the tire because of the heating of the air in the tire is entirely prevented.

I claim.

1. In a pressure indicator, the combination of a support, a pressure indicator mounted on the support and comprising a sleeve and a diaphragm mounted in said sleeve formed of a plurality of flexible sheets, a button operated by said sheets, a stem revolubly connected to said button, a spring toresist the upward movement of said button, and means for turning said stern as it is moved upward against the pressure of said spring.

2. In a pressure indicator, the combination of a diaphragm chamber consisting of a cylindrical tube having an internal shoulder,

- a flexible diaphragm resting on said shoulder, means to hold the diaphragm in position, a button connected to said diaphragm, a. stem mounted on said button and movable longitudinally therewith but revoluble independent thereof, a pin mounted on said stem, a'tube wherein said stem is slidable provided with a spiral slot through which said pin on said stem extends whereby said stem is turned as it is moved longitudinally innsaid tube, an indicating hand at the u per end of the stem and a chamber at t e upper end of said tube wherein said indicating hand is mounted.

3. In a pressure indicator, the combination of a support, a pressure indicator mounted on the support and comprising a sleeve and a diaphragm mounted in said sleeve, a button operated by said'diaphragm, a stem connected to said button, a spring engaging the button to resist the upward movement of said button, means for turning said stem as it is moved upward against the pressure of said spring, and means to adjust the tension of the spring. v

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

EDWARD B. KEITH.

Witnesses:

JOHN Wa'ronroonn'r, Jenna H. Knrrn. 

